I have used X10 for more years than I want to admit... I think I statred with the Radio Shack items in the 1980s. If I had just one or two problems, I would try to solve them here... My guess is that I have a REAL interference issue... All of my stuff works BUT I have had to Mickey Mouse a lot of it. My extensive LED landscape lighting works great on a mini timer.... I have lights in my entry ( a different house code) that work " sometimes" on a plug in controller... I went to a wireless contoller with a transceiver and it works almost always.... Too many issues to worry about... I even had an electrician install an X10 "bridge" years ago hoping it would sove some of my ( works here but not there) issues.
End of story... I need a really sharp X10 Guru to help me out.....

Can one of the forum members suggest an electrician or other Guru in my area who I can hire to take a look at "what I got".

X10 over power line (wired) is just too buggy (IMHO). No electrician can make it work, because it's not the electrician that's the issue, it's the X10 over powerline implementation! Anytime you plug in a component with a large transformer, it will attenuate the X10 signal even more.

I put all of my X10 wired stuff on ebay. Ironically, that's where I bought it from, but I will say I was surprised to get 90% of my money back on most of it! X10 is definitely not worth the labor cost of having an electrician try to get things working 100% of the time (because they can't).

I will admit I still use the X10 RF stuff and I can't really knock the DS10A secure window/door sensor. I use the DS10A to automate things that I can't easily run a wire to like my mailbox. The thing still works and it's seen 110 degree days and lives in a black mailbox?!?

However, I bought a W800RF32 RS232 receiver and built a custom antenna for to improve the range. I also use a lot of palm pads that also work with the W800RF32.

Basically, keep your X10 RF stuff, and ditch the X10 power line (wired stuff) for Z-Wave. With free software such as Motorola Premise, you can seamlessly integrate the two and have a 100% working solution on the cheap. I see less than 1/10000 commands fail when turning my lights on/off, dimming, etc...